The invention is directed to a controllable integrated-optical Mach-Zehnder interferometer formed of two strip waveguides integrated on a substrate, and as proposed in the earlier German patent application P 39 29 131.6 (GR 89 P 1730 DE), incorporated herein.
In the proposed interferometer, the pn-junction or pin-junction extends over the entire length of the two strip waveguides designed as a rib waveguide. These strip waveguides thus have a uniform waveguide structure, whereby the pn-junction or pin-junction is electrically controllable via electrical contacts only in the phase shifting section.
This interferometer can be operated as an optical switch that supplies an optical input signal to the one or to the other output of the switch dependent on an electrical control signal.
In the proposed interferometer, the function of this component is generally dependent on the polarization of the input signal, i.e. TE-polarized input signals are distributed differently onto the outputs than TM-polarized input signals with a given geometry.